Polycrystalline diamond compact (PDC) refers to a superhard composite composed of diamond layer of 0.1mm to several millimeters thickness and cemented carbide substrate under high pressure and high temperature (5-7 GPa, 1400℃-1700℃). PDC has the characteristics of high hardness, high wear resistance modulus, and relatively high thermal conductivity. It has become a kind of preferred material for high-grade machinery and processing tool, geological and petroleum drill bit, ceramic abrasive tool, stone processing tool and concrete tools and other high wear-resistant equipment. And it has become one of the most vital pillars in the field of high-tech new materials. PDC is mostly used in the field of precision machining, and their dimensional tolerance requirements are very strict. Therefore, how to efficiently process PDC has been a big matter. At present, most PDC grinding manufacturers use the diamond grinding wheel to grind PDC with external grinding to achieve the required dimensional tolerance requirements. The processing efficiency and processing accuracy of the resin diamond grinding wheel is much lower than the ceramic bond diamond grinding wheel, so the vitrified bond diamond grinding wheels are used for PDC grinding. In order to meet the growing demand for ceramic diamond grinding wheels in the external cylindrical grinding market, Glory Diamond Tools has carried out research on special ceramic bond diamond grinding wheels for external cylindrical grinding. Through the cooperation with the customers, the preparation and application technology of the ceramic bond diamond grinding wheel for the PDC grinding is greatly improved.
The hardness of the super-hard material grinding wheel refers to the difficulty of the super-hard abrasive falling off from the grinding wheel. The harder it is to fall off, the higher the hardness of the grinding wheel. In general, the more the bond dose, the stronger the abrasive holding. If the hardness of the grinding wheel is too high, the grinding wheel will be difficult to grind. The service life of the grinding will be increased, but the surface of PDC will be chipped. The hardness of PDC itself is very high. During the external grinding process, the diamond on the surface of the grinding wheel is subjected to a large amount of grinding force and impact force. If the ceramic bonding dose is too little, the ceramic bond will not have enough hold force for the diamond, which will lead to falling off of the diamond without fully exerting effect. And the service life will also become short. If the bond is too much, the hardness of the grinding wheel will be too large, and the sharpness will be not enough, which will make PCD chipped.
The control of the firing temperature of the ceramic bond directly affects the performance of the grinding wheel, which is mainly related to the properties of the super-hard abrasive and the ceramic bond itself. In the practice of producing ceramic tool products, we found that the strength of the grinding wheel block will be correspondingly increased when the sintering temperature of the grinding wheel block is increased in the sintering range. The concentration of the superabrasive is the content of the superabrasive in a unit volume in the superabrasive layer. The higher the concentration, the longer the life. As the diamond concentration increases, the life of the grinding wheel increases more. We believe that for the external cylindrical grinding of PDC the diamond abrasive grains involved in grinding in the high-concentration ceramic diamond grinding wheel increase.